Clostridium difficile infection (CDI) is common in pediatric oncology patients and is often associated with recurrences and complications. We hypothesized that higher intensity of chemotherapy would be associated with these outcomes. We conducted a retrospective cohort study including all cases of primary CDI in children with malignancy in our institution for over 7 years. Intensity of chemotherapy was measured by the Intensity of Treatment Rating Scale, third edition, ranging from level 1 (minimal) to 4 (highest). Outcomes included recurrence within both 56 and 180 days, CDI-associated complications, and primary treatment failure (PTF). Risk of recurrence was compared using Cox proportional hazards regression. Among 192 patients with CDI and malignancy, 122 met inclusion criteria. CDI recurred in 27% (31/115) of patients followed for 56 days and 46% (48/104) of patients followed for 180 days. Fourteen patients (11.4%) had a CDI-associated complication, including 4 intensive care unit admissions and 3 surgical procedures, but no deaths. Ten patients (8.2%) had PTF. Although PTF and severe complications were infrequent, recurrence was common in our cohort. None of these outcomes were associated with level of treatment intensity. More research is required to assess oncologic and nononcologic risk factors for CDI recurrence, PTF, and severe CDI-associated complications.